Homebrewers Association  AHA Forum
General Category => All Grain Brewing => Topic started by: bbump22 on April 26, 2010, 05:17:59 PM

I Batch Sparged the other day and by the time I reached my boil volume there was still a decent amount of water remaining in the mash tun. Will the extra sparge water not used have an effect on my Brewhouse Efficiency? ??? I had been averaging around 68%, but this one was down at 57% and all other processes were the same.
Thanks!

I Batch Sparged the other day and by the time I reached my boil volume there was still a decent amount of water remaining in the mash tun. Will the extra sparge water not used have an effect on my Brewhouse Efficiency? ??? I had been averaging around 68%, but this one was down at 57% and all other processes were the same.
Thanks!
Yeah, the water you left in the tun still had dissolved sugars in it so that would impact your efficiency. Next time, you might want to think about going ahead and draining completely and either boiling a little longer or (what I do) pressure can the extra for starters.

Cool, thanks! I need to get my sparge calculation down better and get an accurate volume measurement. I am tempted to buy a kettle with a sight glass just to be more certain of my volume.

Through some trial and error you should be able to develop a pretty consistent feel for the amount of water which will be lost in your system during the mashing and sparging process (grain absorption, dead spaces below the valve, etc). Using this info you should eventually be able to plan out the strike and sparge water quantities to get pretty close to your target boil volume.

Cool, thanks! I need to get my sparge calculation down better and get an accurate volume measurement. I am tempted to buy a kettle with a sight glass just to be more certain of my volume.
There's an even easier way to do it. After you run of the mash, measure how much wort you have in your kettle. Subtract that from your boil volume. The answer you get is how much sparge water to use. Since the grain is already saturated, it won't absorb any more water. The only variable will be any dead space in your mash tun.

The only variable will be any dead space in your mash tun.
Even the dead space won't have any affect, right? After you drain your tun the first time, the dead space is already full so every bit of what you add after that should come out in the second draining, right?

Right!

I always refer to the total volume of cool water that is started with. Account for absorption and boiloff (evaporation). You should collect everything you can since the "wort faeries" can steal away some of the liquid.
When collecting hot wort remember that it also expands plus there is dissolved sugars in it. Relying on the "measuring marks" on the bucket or kettle from premash to preboil will usually give inaccuracies in the end.
So if you've calculated your absorption for the grain and hops; evaporation and deadspace arriving at a specific volume, leaving wort in the tun will result in being short postboil when batchsparging.

I always refer to the total volume of cool water that is started with. Account for absorption and boiloff (evaporation). You should collect everything you can since the "wort faeries" can steal away some of the liquid.
When collecting hot wort remember that it also expands plus there is dissolved sugars in it. Relying on the "measuring marks" on the bucket or kettle from premash to preboil will usually give inaccuracies in the end.
So if you've calculated your absorption for the grain and hops; evaporation and deadspace arriving at a specific volume, leaving wort in the tun will result in being short postboil when batchsparging.
Euge, if you have a chance, would it be possible to give me an example of how you would go about calculating the total volume of cool water to start with? How much water would you mash with and then how much you would batch sparge with to get your preboil volume? Assuming you mashed 9 lbs of grain and wanted to end up with a batch size of 3.5 gallons.
If you have the time, I would appreciate it...this is the one variable of my brewing that is giving me the most trouble right now.
Thanks!

I always refer to the total volume of cool water that is started with. Account for absorption and boiloff (evaporation). You should collect everything you can since the "wort faeries" can steal away some of the liquid.
When collecting hot wort remember that it also expands plus there is dissolved sugars in it. Relying on the "measuring marks" on the bucket or kettle from premash to preboil will usually give inaccuracies in the end.
So if you've calculated your absorption for the grain and hops; evaporation and deadspace arriving at a specific volume, leaving wort in the tun will result in being short postboil when batchsparging.
Euge, if you have a chance, would it be possible to give me an example of how you would go about calculating the total volume of cool water to start with? How much water would you mash with and then how much you would batch sparge with to get your preboil volume? Assuming you mashed 9 lbs of grain and wanted to end up with a batch size of 3.5 gallons.
If you have the time, I would appreciate it...this is the one variable of my brewing that is giving me the most trouble right now.
Thanks!
Also, I dont have a false bottom in my MT and I just tilt my MT to try to make sure I draw most of the water out. Generally there is less than about a cup or 2 remaining, if that.

Euge, if you have a chance, would it be possible to give me an example of how you would go about calculating the total volume of cool water to start with? How much water would you mash with and then how much you would batch sparge with to get your preboil volume? Assuming you mashed 9 lbs of grain and wanted to end up with a batch size of 3.5 gallons.
If you have the time, I would appreciate it...this is the one variable of my brewing that is giving me the most trouble right now.
Thanks!
bbump22, from my website at www.dennybreww.com....
The main concept we’re going to be working with is that for the best efficiency, the runoff volumes from your mash and batch sparge should be equal. In order to do that, it’s sometimes necessary to infuse your mash with extra water before thefirst runoff. Here’s how it works...
R1=initial runoff volume which = mash water volume  water absorbed by grain
(assumed to be .1 gal./lb. for this example since that’s the way my system works...use your own figure)
S= batch sparge water volume
V= total boil volume (amount in needed in kettle for boil)
I=volume of infusions for a step mash
R1+I+S(1)+S(2)+S(etc.) must equal V
AND
R1+I=.5V
Let’s see how this works in a brewing session. Assume a recipe with 10 lb. of grain, and that you need to collect 7 gal. of pre boil wort. A mash ration of 1.25 qt./lb. would require 12.5 qt. or 3.125 gal. of strike water. Based on an absorption of .1 gal./lb., the mash would absorb 1 gal. of water so we’d get 2.125 gal. of water from the mash. Since we want to collect 3.5 gal. (or 50% of the boil volume), after the mash is complete we’d add 1.375 gal. (5.5 qt.) of water to mash tun before the first runoff. Stir the additional water in, let it sit for a few minutes, then vorlauf until clear and start your runoff. After the runoff, we add 3.5 gal. of batch sparge water. Stir it in well, then vorlauf and runoff as before. These two runoffs will give us our pre boil volume of 7 gal. of sweet wort.

Euge, if you have a chance, would it be possible to give me an example of how you would go about calculating the total volume of cool water to start with? How much water would you mash with and then how much you would batch sparge with to get your preboil volume? Assuming you mashed 9 lbs of grain and wanted to end up with a batch size of 3.5 gallons.
If you have the time, I would appreciate it...this is the one variable of my brewing that is giving me the most trouble right now.
Thanks!
bbump22, from my website at www.dennybreww.com....
The main concept we’re going to be working with is that for the best efficiency, the runoff volumes from your mash and batch sparge should be equal. In order to do that, it’s sometimes necessary to infuse your mash with extra water before thefirst runoff. Here’s how it works...
R1=initial runoff volume which = mash water volume  water absorbed by grain
(assumed to be .1 gal./lb. for this example since that’s the way my system works...use your own figure)
S= batch sparge water volume
V= total boil volume (amount in needed in kettle for boil)
I=volume of infusions for a step mash
R1+I+S(1)+S(2)+S(etc.) must equal V
AND
R1+I=.5V
Let’s see how this works in a brewing session. Assume a recipe with 10 lb. of grain, and that you need to collect 7 gal. of pre boil wort. A mash ration of 1.25 qt./lb. would require 12.5 qt. or 3.125 gal. of strike water. Based on an absorption of .1 gal./lb., the mash would absorb 1 gal. of water so we’d get 2.125 gal. of water from the mash. Since we want to collect 3.5 gal. (or 50% of the boil volume), after the mash is complete we’d add 1.375 gal. (5.5 qt.) of water to mash tun before the first runoff. Stir the additional water in, let it sit for a few minutes, then vorlauf until clear and start your runoff. After the runoff, we add 3.5 gal. of batch sparge water. Stir it in well, then vorlauf and runoff as before. These two runoffs will give us our pre boil volume of 7 gal. of sweet wort.
Once again, Denny to the rescue! Thanks man  I appreciate it and I have also bookmarked your website.

What Denny said... ;D
Bbump32
Consider that you start with a given amount of water and expect to end up with another. My initial difficulties were relying on volume measurement during the varying stages of the brewing process. Now I don't worry about it until the wort goes into the fermenter. Mysterious extra gallons of hot water were cause for concern, and I found if they weren't included then my final volume was always short and my gravity way off. :P
From experience I know what it takes to get 12 gallons out of my system usually my beers use about #25 of grain. Fill the kettle up nearly to the top, about 1718 gallons. Absorption and evaporation during the process and boil leaves me with 12 gallons. I've done the water calculations for many batches, but now I just fill and brew. ;)

What Denny said... ;D
Bbump32
Consider that you start with a given amount of water and expect to end up with another. My initial difficulties were relying on volume measurement during the varying stages of the brewing process. Now I don't worry about it until the wort goes into the fermenter. Mysterious extra gallons of hot water were cause for concern, and I found if they weren't included then my final volume was always short and my gravity way off. :P
From experience I know what it takes to get 12 gallons out of my system usually my beers use about #25 of grain. Fill the kettle up nearly to the top, about 1718 gallons. Absorption and evaporation during the process and boil leaves me with 12 gallons. I've done the water calculations for many batches, but now I just fill and brew. ;)
One day I hope to be able to just fill and brew too!
Denny, after the mash is complete and adding additional 1.375 Gal of water to compensate for absorbtion, what temperature should that water be heated to?

Denny, after the mash is complete and adding additional 1.375 Gal of water to compensate for absorbtion, what temperature should that water be heated to?
Ideally, you'd like to heat your "mash out" water to whatever temperature it requires to raise your mash temp to just below 168F. Brewing software usually has some sort of "mash calculator" function that'll allow you to figure out what that temp is. I know BeerSmith that I use has that feature.

One day I hope to be able to just fill and brew too!
Denny, after the mash is complete and adding additional 1.375 Gal of water to compensate for absorbtion, what temperature should that water be heated to?
I generally go anywhere form 190 to boiling. I also don't bother with that extra "pre mash runoff" addition as often as I used to. I've found that if that addition looks to be a gal. or less, there isn't much benefit gained by adding it. Being lazy, I'd just as soon skip it if I can!

One day I hope to be able to just fill and brew too!
Denny, after the mash is complete and adding additional 1.375 Gal of water to compensate for absorbtion, what temperature should that water be heated to?
I generally go anywhere form 190 to boiling. I also don't bother with that extra "pre mash runoff" addition as often as I used to. I've found that if that addition looks to be a gal. or less, there isn't much benefit gained by adding it. Being lazy, I'd just as soon skip it if I can!
When I read a mash directions such as this "Mash in at 145° F (63° C) and hold for 60 minutes. Slowly raise the mash temperature to 169° F (76° C), then sparge with 173° F (78° C) water." How would I slowly raise the mash temp to 169? Also, what is considered "slowly"? I also get confused when it says to sparge with 173 degree water...This means the grain bed should be raised to 173, right? So I would adjust my sparge water appropriately then.

When I read a mash directions such as this "Mash in at 145° F (63° C) and hold for 60 minutes. Slowly raise the mash temperature to 169° F (76° C), then sparge with 173° F (78° C) water." How would I slowly raise the mash temp to 169? Also, what is considered "slowly"? I also get confused when it says to sparge with 173 degree water...This means the grain bed should be raised to 173, right? So I would adjust my sparge water appropriately then.
You don't go "slowly"...it just doesn't matter. Really, it doesn't matter all that much of you even go to the 169 step. Generally, your sparge water will need to be hotter than the final temp you're shooting for. For instance, if I want to hit that 169 step, I need to use water from 190boiling in order to raise the grain bed temp from the mash temp. The lower your mash temp, the hotter the sprage water will need to be in order to hit the 169 temp.

Cool, thanks! I need to get my sparge calculation down better and get an accurate volume measurement. I am tempted to buy a kettle with a sight glass just to be more certain of my volume.
I'm with on that. I'll just add one to my keg though. If you can't accurately measure your water, you can't calculate efficiency. I "guess" I'm between 6070%. But it's a total guess.

To measure the volume on my brewpot I just used a wooden dowel which I marked with a pencil. Nothing fancy but it gets the job done with reasonable accuracy and consistency.
Also I'd recommend keeping track as best you can all your volume measurements for a while. This will help you better understand how your system operates, which is really what it all comes down to. Once you get used to things you'll find you have to think about it alot less to get the desired results.